This invention relates to a thermal container, thermal insulating liners for such a container, and dies for making the thermal insulating liners.
Perishable goods may be packed in containers for shipping that utilize materials such as waxed corrugate and expanded polystyrene (STYROFOAM™). A refrigerant may be placed in the container with the goods. For example, it is known to pack fresh fish in a bag, surround the bag with a frozen Gel-Pack or ice, and place the bag and refrigerant in a corrugated container lined with polystyrene sheets as insulation. While such a thermally insulated container will keep the container contents acceptably refrigerated for a period of time, shipping times may exceed this time period. Further, expanded polystyrene gives rise to a health risk as styrene can leach from the material. Moreover, expanded polystyrene poses environmental concerns: it is a problem in landfills and has been banned from landfills in a number of cities and, being petroleum based, it is not a sustainable product.
U.S. Pat. Nos. 5,000,372 and 5,111,957 attempt to improve the insulating properties of a container by using panels formed of a honeycomb material covered by aluminum foil. However, the described containers are susceptible to leaking and there also remains a need for a thermal container which maintains its contents in a refrigerated state for a longer time period.